ASoC: tegra: sort Makefile into common and per-SoC files

The DAS, I2S, and SPDIF drivers are Tegra20-specific. Group these
together so that when Tegra30-specific equivalents are added later, the
file ordering makes sense.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/tegra/Makefile

 # Tegra platform Support
-snd-soc-tegra-das-objs := tegra_das.o
 snd-soc-tegra-pcm-objs := tegra_pcm.o
+snd-soc-tegra-utils-objs += tegra_asoc_utils.o
+snd-soc-tegra-das-objs := tegra_das.o
 snd-soc-tegra-i2s-objs := tegra_i2s.o
 snd-soc-tegra-spdif-objs := tegra_spdif.o
-snd-soc-tegra-utils-objs += tegra_asoc_utils.o
 
+obj-$(CONFIG_SND_SOC_TEGRA) += snd-soc-tegra-pcm.o
 obj-$(CONFIG_SND_SOC_TEGRA) += snd-soc-tegra-utils.o
 obj-$(CONFIG_SND_SOC_TEGRA_DAS) += snd-soc-tegra-das.o
-obj-$(CONFIG_SND_SOC_TEGRA) += snd-soc-tegra-pcm.o
 obj-$(CONFIG_SND_SOC_TEGRA_I2S) += snd-soc-tegra-i2s.o
 obj-$(CONFIG_SND_SOC_TEGRA_SPDIF) += snd-soc-tegra-spdif.o